Described in Australian Patent Application 64365/96 (U.S. Pat. No. 5,779,888) is an apparatus to filter litter from waterways, particularly stormwater systems.
The above discussed filter apparatus is most suited to applications in which there is a substantial head of water.
Many stormwater systems may not have at low flow rates, the preferable head of water required by the apparatus of the above Australian application.
Other filter apparatuses are described in Patent Specification Nos. GB2267, WO 94/17896, U.S. Pat. No. 4,801,377 and DE 2743580. Essentially, the filter apparatus described in these specifications do not address problems associated with low flow rates, and more particularly flow rates having a low head.
Further filter apparatuses are described in U.S. Pat. Nos. 4,081,374 and 5,141,650. The filter apparatus of these two specifications does not relate to the field of removing litter from stormwater systems. They do not address the problems associated with flow rates having a low head in stormwater systems. U.S. Pat. Nos. 5,232,587, 3,282,430, 1,825,169, 2,106,851, 3,123,455 and 5,531,888. Again the filter apparatus described in these specifications does not address the problems associated with stormwater systems having a low head.